diff options
Diffstat (limited to 'doc/documentation.tex')
| -rw-r--r-- | doc/documentation.tex | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/doc/documentation.tex b/doc/documentation.tex index e27881f..51ebda7 100644 --- a/doc/documentation.tex +++ b/doc/documentation.tex @@ -35,12 +35,16 @@ The general idea is that codes which use boundary conditions, be they physical or symmetry conditions, need not know anything about the thorns which provide them. +This thorn also contains some standard boundary conditions, most of which +can be used with any spatial dimension and data type. + \subsection{Local and non-local boundary conditions} Boundary conditions can be \emph{local}, meaning that the boundary point can be updated based on data in its immediate vicinity, or \emph{non-local}, meaning that the new value on the boundary depends -on data from a remote region of the computational domain. An example +on data from a remote region of the computational domain (for a parallel +simulation this data could for example be physically located on several different processors). An example of the latter is a ``rotating'' symmetry condition, which arises e.g.~when one uses a quadrant to simulate a physical domain which possesses a rotational symmetry. @@ -52,7 +56,7 @@ the computational domain as a subregion of some larger domain which possesses symmetries. These symmetries allow a simulation of the subregion to act as an effective simulation of the larger encompassing domain, because the latter can be inferred from the former via the -symmetry. For example, one can simulate a rotating star by +symmetry. For example, one can often simulate a rotating star by `slicing' the space in half through the equatorial plane, simulating only one half, and placing a reflection boundary condition at this plane. The symmetry can be regarded as a property of the |